Analysis of root coverage esthetic score in patients treated for gingival recession: An interexaminer reliability.

BACKGROUND: Awareness about pink esthetics among dentists in general needs to be assessed as root coverage procedures are the mainstay of treatment for gingival recession. Concordance among the dentists in figuring out the esthetic outcomes after root coverage procedures is inconsistent. Hence, this study aims to evaluate inter- and intra-examiner reliability of root coverage esthetic scores (RES) between periodontists and nonperiodontists.
MATERIALS AND METHODS: The study was conducted using twenty baseline and 6-month posttreatment photographs of Miller's Class I and Class II gingival recessions. The participants that constituted ten periodontists and ten nonperiodontists were assembled in the seminar hall to receive training on protocol and procedures for RES by the investigator. All the participants were shown twenty projections of side-by-side baseline and 6-month outcomes of root coverage procedures. Each projection was shown for 30 s during which the participants were made to use RES system to evaluate the surgical outcomes.
RESULTS: Periodontists showed the highest reliability in the scores of marginal tissue contour with an overall intraexaminer reliability to be perfect among periodontists. Intraexaminer reliability among nonperiodontists was fair, and gingival margin was the parameter with the highest reliability among them. Interexaminer reliability between periodontists and nonperiodontists showed slight reliability concerning gingival margin, and fair reliability was found for marginal tissue contour, soft-tissue texture, mucogingival junction, and gingival color.
CONCLUSION: Satisfying the esthetic component of gingiva is the duty of every dentist in general and not only the periodontists. Significant variability was found in esthetic scores between the groups, which can probably be attributed to the lack of sufficient knowledge regarding pink esthetics among the nonperiodontists, which needs to be improved. Copyright:

INTRODUCTION

Esthetics refers to the beauty of an individual. As there has been a rise in the esthetic awareness among the patients in recent times, it signifies the need for improvement in standards of treatment. Similarly, the stringent esthetics demands of the patients become highly crucial when it comes to the esthetic zone. The esthetic zone is the visible area seen upon a full smile, which includes teeth, gingiva, and lips.[1] Hence, an upgradation in the sphere of periodontics from being strictly a health-related service to the one which gifts optimal esthetics can be observed in the existing scenario.

Esthetic concern is a primary indication for treatment of gingival recession (AAP 1996).[2] The ultimate goal of any periodontal plastic surgery is directed to treat gingival recession with predictable recession coverage and esthetic outcome.[3] Mucogingival surgical procedures are thus designed to correct defects in the morphology, position, and the amount of gingiva among which unesthetic appearance of the exposed root surfaces are taken care of.[4] These root coverage procedures should aim to provide soft-tissue anatomy that is comparable to and indistinguishable from adjacent tissue. In the last decade, a large amount of data have shown that different procedures are effective in obtaining root coverage.[2] Achieving esthetic periodontal treatment outcome is highly challenging as satisfying the degree of root coverage, the contour of the marginal gingiva, color match, alignment of the mucogingival junction (MGJ), and soft-tissue texture are inevitable parameters for achieving an optimal esthetic outcome.

With regard to the esthetic sense, although a general dentist is trained in all aspects to provide esthetics concerning the shape of the teeth, the color of the teeth, etc., his knowledge is limited to white esthetics and is not in par with a periodontist as far as pink esthetics is concerned. Hence, this study was undertaken to compare and analyze the esthetic judgment between periodontists and nonperiodontists after observing the pre- and post-operative pictures of root coverage procedures using root coverage esthetic score (RES).[5]

MATERIALS AND METHODS

Sample size calculation

Sample size calculation was done using G power 3.1 software. The calculations were based on effect size 1.26, an alpha level of 0.05, the desired power of 80%, and a confidence interval (CI) of 95%. The estimated desired total sample size in the study was 20. The sample size of 20 in the article was chosen based on the key article.[6]

Source of the data

Twenty photographs of treated Millers Class I and Class II gingival recession which were taken at baseline and 6 months were collected. Ten periodontists and ten nonperiodontists were recruited for scoring the root coverage procedure outcomes using RES.

Selection criteria

Twenty baseline and 6-month posttreatment photographs of Miller's Class I and Class II gingival recession were included in the study. Photographs that lacked focus, those which displayed distortion, and those which displayed poor color and contrast were excluded from the study.

Study design

Participants were grouped into two categories: periodontists and nonperiodontists. They were assembled in the seminar hall to receive training on protocol and procedures for RES[5] by the investigator. The participants were given a brief overview of the soft-tissue component around the teeth and the parameters that need to be observed for. The participants were explained about the elements in the scoring system given by Cairo et al.[5] which has been depicted in Table 1.

Table 1

Root coverage esthetic scoring system given by Francesco Cairo

Parameters	Scores
GM	Score 0: Failure of root coverage (gingival margin apical or equal to the baseline recession)
	Score 3: Partial root coverage
	Score 6: Complete root coverage
MTC	Score 0: Irregular gingival margin
	Score1: Proper marginal contour/scalloped gingival margin (follows CEJ)
STT	Score 0: Scar formation and/or keloid like appearance
	Score 1: Absence of scar or keloid formation
MGJ	Score 0: MGJ not aligned with MGJ of adjacent teeth
	Score 1: MGJ aligned with MGJ of adjacent teeth
GC	Score 0: Color of tissue varies from gingival color at adjacent teeth
	Score 1: Normal color and integration with the adjacent soft tissues

GM – Gingival margin; MTC – Marginal tissue contour; STT – Soft-tissue texture; MGJ – Mucogingival junction; GC – Gingival color; CEJ – Cementoenamel junction

They were given a worksheet that asked for demographic information, information about the participant's profession and contained a data collection scoring sheet. All the participants were shown twenty projections of side-by-side baseline and 6-month outcomes of root coverage procedures [Figures 1-4]. Each projection was shown for 30 s during which the participants were asked to use RES system to evaluate the surgical outcomes. The results were then recorded on a standardized scoring grid.

Figure 1

Baseline photograph of Class II gingival recession in relation to 41

Figure 2

Six-month postoperative photograph of Class II gingival recession in relation to 41. RES: GM-3, MTC-0, STT-1, MGJ-1, GC-1. RES – Root coverage esthetic scores; MTC – Marginal tissue contour; STT – Soft-tissue texture; MGJ – Mucogingival junction; GC – Gingival color

Baseline photograph of Class I gingival recession in relation to 23

Six-month postoperative photograph of Class I gingival recession in relation to 23. RES: GM-3, MTC-0, STT-1, MGJ-1, GC-1. RES – Root coverage esthetic scores; MTC – Marginal tissue contour; STT – Soft-tissue texture; MGJ – Mucogingival junction; GC – Gingival color

A six-level nomenclature was used to assess the level of agreement: poor agreement = <0.00, slight agreement = 0.00–0.20, fair agreement = 0.21–0.40, moderate agreement = 0.41–0.60, substantial agreement = 0.61–0.80 and almost perfect agreement = 0.81–0.92.[7]

Statistical analysis

All the data obtained after projecting the photographs were computed and analyzed. Statistical analysis was done using interclass correlation coefficient (ICC) and independent t-test.

RESULTS

Intraexaminer reliability among periodontists

Among periodontists, the parameter of the gingival margin showed an ICC of 0.898 (95% CI: 0.762–0.959), which depicts that they have a perfect correlation in deciding the amount of root coverage. When the values of marginal tissue contour were assessed, the ICC was 1.00 (95% CI: 1.00), which shows that there is absolutely perfect reliability in examining the tissue contours. The ICC of soft-tissue texture which was 0.835 (95% CI: 0.629–0.931), also showed perfect reliability. Moderate reliability was found in the scores of MGJ with ICC = 0.541 (0.141–0.789). Substantial reliability was recognized with scores of gingival color with an ICC = 0.655 (95% CI: 0.309–0.847). However, an overall assessment of scores of periodontists proved to have a perfect correlation with ICC = 0.869 (95% CI: 0.700-0.946) as shown in Table 2.

Table 2

Intraexaminer reliability among periodontists

Parameter	ICC	95% CI	Reliability
GM	0.898	0.762-0.959	Perfect
MTC	1.000	1.000	Perfect
STT	0.835	0.629-0.931	Perfect
MGJ	0.541	0.141-0.789	Moderate
GC	0.655	0.309-0.847	Substantial
Total	0.869	0.700-0.946	Perfect

ICC – Interclass correlation; CI – Confidence interval; GM – Gingival margin; MTC – Marginal tissue contour; STT – Soft-tissue contour; MGJ – Mucogingival junction; GC – Gingival color

Intraexaminer reliability among nonperiodontists

When considering only nonperiodontists, ICC concerning gingival margin was 0.296 (95% CI: 0.157–0.646), which shows that they had fair reliability. When it comes to marginal tissue contour, ICC was 0.00 (95% CI: 0.00), which shows absolutely poor reliability among them. Soft-tissue texture had an ICC of 0.18 (95% CI: 0.569–0.274) that reveals slight reliability. A similar level of reliability was found with respect to MGJ and gingival color with an ICC of 0.132 (95% CI: 319–0.535) and 0.209 (95% CI: 0.588–0.246), respectively. On an overall basis, it was found that nonperiodontists had fair reliability within themselves with ICC = 0.217 (95% CI: 0.238–0.594) as depicted in Table 3.

Table 3

Intraexaminer reliability among nonperiodontists

Parameter	ICC	95% CI	Reliability
GM	0.296	0.157-0.646	Fair
MTC	0.000	0.000	Poor
STT	0.18	0.569-0.274	Slight
MGJ	0.132	0.319-0.535	Slight
GC	0.209	0.588-0.246	Slight
Total	0.217	0.238-0.594	Fair

ICC – Inter class correlation; CI – Confidence interval; GM – Gingival margin; MTC – Marginal tissue contour; STT – Soft-tissue contour; MGJ – Mucogingival junction; GC – Gingival color

Interexaminer reliability between periodontists and nonperiodontists

On comparing the gingival margin scores between periodontists and nonperiodontists, the variability was found to be very high with ICC of 0.099 (95% CI: 0.349–0.510) that corresponds to slight reliability. A fair reliability was reported on calculating the ICC scores for the parameters of marginal tissue contour, soft-tissue texture, MGJ, and gingival color which were 0.302 (95% CI: 0.151–0.650), 0.238 (95% CI: 0.608–0.217), 0.294 (95% CI: 0.645–0.159), and 0.386 (95% CI: 0.059–0.701), respectively. Finally, the interexaminer reliability was assessed after examining all the scores which helped us to arrive at a conclusion that there exists a fair reliability (ICC: 0.312, 95% CI: 0.139–0.657) of the RES when compared between periodontists and nonperiodontists, which is represented in Table 4.

Table 4

Interexaminer reliability between periodontists and nonperiodontists

Parameter	ICC	95% CI	Reliability	P
GM	0.099	0.349-0.510	Slight	0.006
MTC	0.302	0.151-0.650	Fair	0.584
STT	0.238	0.608-0.217	Fair	0.818
MGJ	0.294	0.645-0.159	Fair	0.623
GC	0.386	0.059-0.701	Fair	0.031
Total	0.312	0.139-0.657	Fair	0.222

P<0.05 was considered statistically significant. ICC – Inter class correlation; CI – Confidence interval; GM – Gingival margin; MTC – Marginal tissue contour; STT – Soft-tissue contour; MGJ – Mucogingival junction; GC – Gingival color; P – Probability value

DISCUSSION

The importance of esthetics has immensely increased over the centuries, and modern society has been keen on showing a great interest in esthetic appearance. Esthetic perceptions are intrinsically subjective and depend remarkably on various factors such as socioeconomic status and gender. The judgment about a clinical result may differ considerably between professionals of different specialties.[8] Pink esthetic dentistry embraces comprehensive knowledge of facial esthetics and restorative techniques, combined with detailed patient and interdisciplinary communication, to generate the supporting periodontal structures that have been lost due to periodontal disease and/or gingival recession which can bring about esthetic deficiencies.[9] Being periodontists, sharp focus on gingival esthetics can be guaranteed as their observation is directed more toward gingiva because they are trained to precisely observe the gingival health and esthetics.[10] Therefore, there is a need to analyze the proximity of opinions regarding esthetic perceptions and to know the dependability of their esthetic scores in both groups.

Gingival recessions hinder the esthetic appearance of the patient, for which root coverage procedures are performed in such a way that they provide esthetically pleasing results.[111213] Literature has shown a number of methods for assessing the results of root coverage procedures.[141516] The RES system put forth by Cairo et al., in the year 2009, has incorporated all the parameters that ultimately help us to determine esthetic treatment outcome.[517] The European Survey on Criteria of Aesthetics for Periodontal Evaluation, a multicenter study, recently conducted by Le Roch et al., among the faculty and students, revealed no statistically significant difference between the scores of before-after scoring system and RES among the faculty. Similarly, no difference was seen when RES and pink esthetic score were evaluated. However, students also showed no difference between the scoring systems.[10]

A similar study was conducted by Kerner et al. to evaluate the reliability of professional qualitative scoring methods used for the evaluation of esthetic results after root coverage procedures and to evaluate the relationship between subjective and objective measurements.[16] The observers included in this study were periodontists, prosthodontists, and nurses. The investigator incorporated two different methods of scoring. In the before-after panel scoring system, observers evaluated the difference between pre- and postoperative views, whereas in the random panel scoring system, observers rated each photograph independently. Results of this study showed that, in both the methods, intrarater agreement ranged from substantial to almost perfect for the periodontists. The best interrater agreement was found for trained periodontists using the five-point ordinal scale of the before-after panel scoring system.

Based on the classification of Landis and Koch,[7] the RES may be considered a good instrument to evaluate the esthetic outcomes of root coverage procedures, which was incorporated in our study to estimate the reliability between both our study groups.

Our study results revealed that about 95% match in scores was found among periodontists for gingival margin. This could be correlated with the study conducted by Cairo et al., wherein the assessment of gingival margin was proved to be more reliable among raters.[17] This could be due to the relative simplicity of visualizing and comparing the position of the gingival margin on the pre- and post-treatment photographs. In contrast, only about 40%–50% match was seen among nonperiodontists regarding gingival margin, which shows fair reliability on the scores given by nonperiodontists. Almost similar kind of reliability was noticed among nonperiodontists for other parameters also such as marginal tissue contour, soft-tissue texture, gingival color, and MGJ. Much variability was found among the scores given by nonperiodontists that raises a question of whether we can rely on the esthetic scores given by them or not.

The present study showed the highest interexaminer reliability in “gingival color” which is in accordance with the results of the study conducted by Isaia et al., wherein highest interexaminer reliability was found between Doctor of Medicine in Dentistry (DMD) students, postgraduate residents, and postgraduate faculty with respect to gingival color.[6] Highest variation was found in the scores of a gingival margin between the two groups of this study which shows the inability of the nonperiodontists to assess the degree of root coverage achieved. This can be attributed to the level of experience between periodontists and nonperiodontists of our study, in a similar way to that of DMD students, postgraduate residents, and postgraduate faculty with varying levels of experience in the field of periodontics.

Assessment of marginal tissue contour was found to be perfect among periodontists which are contrary to the results obtained among nonperiodontists that reveal poor reliability. The soft-tissue parameter of RES displayed fair agreement between the periodontists and nonperiodontists of this study which is similar to the level of agreement between DMD students, PG residents, and PG faculty. This could be probably due to the use of photographs which might have influenced the examiner's self-perception during the assessment of soft-tissue characteristics. Analysis of MGJ within periodontists was found to be moderate, which is in association with the study conducted by Cairo et al. that also showed a moderate agreement within the raters.[17] This may be attributed to the difficulty in evaluating the alignment of MGJ with adjacent teeth on photographs.

In the current study, periodontists showed the highest tendency to agree with each other, which proved perfect correlation. This itself offers great reliability on the scores among periodontists as the meticulous training undergone by them on pink esthetics contributes to their ability to examine esthetics in almost the same level, whereas nonperiodontists depicted fair reliability among them which can clearly conclude that their knowledge regarding esthetics is highly subjective from person to person and their scores cannot be relied upon easily.

The results of the present study reveal that there is more closeness in the esthetic scores given by periodontists which are not true in the case of nonperiodontists.

Experience of the evaluators in root coverage procedures is a confounding factor as the perceptions were taken from both periodontists and nonperiodontists with varying levels of experience. However, a larger sample size is recommended to generalize the findings of this study.

More studies can be performed in this aspect with a larger sample size, and we also suggest the inclusion of patients' level of satisfaction after root coverage procedures in addition to their correlation with clinicians' scores.

CONCLUSION

Rising demands toward esthetics display the need for sound esthetic knowledge among the dental fraternity for attaining an attractive and harmonious smile. As periodontists are exclusively trained on soft tissues, their knowledge regarding pink esthetics is far beyond that of general dentists. We could prove this statement right with this study which showed overall perfect reliability among periodontists. Their scores were in contrast with that of nonperiodontists who showed fair reliability among them. Significant variability was found in esthetic scores between these two groups, which can be attributed to the lack of sufficient knowledge regarding pink esthetics among nonperiodontists. At this point, it is not only time to sensitize the dental professionals but also the need of the hour to upgrade their knowledge about esthetics by considering the current patient demands so that a patient can easily rely upon them for satisfying their esthetic needs.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.